## 1. 什么是責任鏈設計模式
## 2. 如何使用責任鏈設計模式
## 3. 代碼
public abstract class AbstractRequest {
private Object object;
public AbstractRequest(Object object) {
this.object=object; }
/**
* 具體的內容對象
* @return
*/
public Object getContent() { return object; }
/**
* 獲取請求級別
*/
public abstract int getRequestLevel();
}
public class Client {
public static void main(String[] args) {
Handler handler1=new Hander1();
Handler handler2=new Handler2();
Handler handler3=new Handler3();
handler1.nextHandler=handler2;
handler2.nextHandler=handler3;
AbstractRequest request3=new Request2("請求1");
AbstractRequest request4=new Request3("請求2");
handler1.handleRequest(request3);
handler2.handleRequest(request4);
}
}
public class Hander1 extends Handler {
@Override
public void handle(AbstractRequest abstractRequest) {
System.out.println("----handle1 處理請求: "+abstractRequest.getRequestLevel()); }
@Override
public int getHandleLevel() {
return 1;
}
}
public abstract class Handler {
public Handler nextHandler;
public void handleRequest(AbstractRequest abstractRequest) {
if (getHandleLevel() == abstractRequest.getRequestLevel()) {
handle(abstractRequest);
} else {
if (nextHandler != null) { nextHandler.handleRequest(abstractRequest);
} else { System.out.println("----> 所有的處理對象都不能處理它"); }
}
}
/**
* 每個處理者的對象的具體處理方式
* @param abstractRequest
*/
public abstract void handle(AbstractRequest abstractRequest);
/**
* 每個處著對象處理的級別
* @return
*/
public abstract int getHandleLevel();
}
public class Handler2 extends Handler {
@Override
public void handle(AbstractRequest abstractRequest) {
System.out.println("----handle2 處理請求: "+abstractRequest.getRequestLevel());
}
@Override
public int getHandleLevel() {
return 2;
}
}
public class Handler3 extends Handler{
@Override
public void handle(AbstractRequest abstractRequest) {
System.out.println("----handle3 處理請求: "+abstractRequest.getRequestLevel());
}
@Override
public int getHandleLevel() {
return 3;
}
}
public class Request1 extends AbstractRequest {
public Request1(Object object) {
super(object);
}
@Override
public int getRequestLevel() {
return 1;
}
}
public class Request2 extends AbstractRequest {
public Request2(Object object) {
super(object);
}
@Override
public int getRequestLevel() {
return 2;
}
}
public class Request3 extends AbstractRequest {
public Request3(Object object) {
super(object);
}
@Override
public int getRequestLevel() {
return 3;
}
}
